Fig. 2. Increased fibronectin matrix assembly by WI-38 (VA13) cells on a 3D fibronectin matrix. WI-38(VA13) cells were seeded on 3D matrix prepared from NIH3T3 cells (3D) or on surfaces coated with 10 µg/ml rat pFN (2D). (A) DOC lysates were prepared at the indicated times. DOC-insoluble samples were analyzed on 5% polyacrylamide-SDS gels and immunoblotted with HFN7.1. (B) Cells were seeded in 24-well dishes at the indicated cell densities. After incubation for 6 hours, DOC-insoluble samples were prepared and analyzed as described in A. (C) WI-38 (VA13) cells seeded for 8 hours on 3D matrix (3D, left) or fibronectin-coated coverslips (2D, right) were fixed and immunostained with HFN7.1 followed by fluorescein goat anti-mouse IgG. (D) DOC-insoluble fibronectin matrix formed by WI-38 human lung fibroblasts (left) and human dermal fibroblasts (right) was analyzed at 8 hours as in A. Bar, 20 µm.